Scientists are always studying the methods animals use to obtain food. Foraging often involves more than finding food in the open or running it down. Sometimes it requires the use of tools and adapting the way they use tools. Crows can use a tool to pry the lid off a milk bottle, and seagulls can crack open clam shells by dropping them on rocks from high elevations. In a recent study, biologists observed ants adapting tool use to obtain food.
Researchers found that black imported fire ants (Solenopsis richteri) can use sand to adapt their method of reaching a food source. Researchers filled small containers with sugar water, a favorite food for the ants. This species of ants have hydrophobic exoskeletons, which allow them to float on the water to reach the food. However, when the scientists added a surfactant to reduce the surface tension, the ants sank and drowned.
That was the point where the scientists saw the ants adapting tool use. The researchers provided the ants with sand in various grain sizes. They allowed the ants to choose a way to reduce their drowning risk. One of the study authors, Dr. Aiming Zhou, said, “We found the ants used sand to build a structure that could effectively draw sugar water out of the container to then be collected.” Dr. Jian Chen, another author of the research, said, “We knew some ant species are able to use tools, particularly in collecting liquid food; however, we were surprised by such remarkable tool use displayed by black imported fire ants.”
It is difficult to believe that the ants have a brain that could reason this out, and they did not display trial and error behavior. The response was immediate and indicated that built into the ant’s DNA is something that enables them to secure food. Entomologist Jian Chen wrote, “Our findings suggest that ants and other social insects may have considerable high cognitive capabilities for unique foraging strategies.” Previously cognitive sophistication has been observed in primates and birds, but scientists had thought the behavior was “hard wired” in invertebrates. These ants adapting tool use seems to defy that understanding. According to Dr. Chen, “Our study is the first to touch on this interesting topic.”
We would suggest that the ants’ Creator designed them to live in a wide variety of environments and built the tools into their genetics that would allow them to do that.
— John N. Clayton © 2020